Merge pull request #917 from tendermint/trust-metric-cleanup

Trust metric cleanup

p2p/trust/config.go

@@ -0,0 +1,56 @@
+package trust
+
+import "time"
+
+// TrustMetricConfig - Configures the weight functions and time intervals for the metric
+type TrustMetricConfig struct {
+	// Determines the percentage given to current behavior
+	ProportionalWeight float64
+
+	// Determines the percentage given to prior behavior
+	IntegralWeight float64
+
+	// The window of time that the trust metric will track events across.
+	// This can be set to cover many days without issue
+	TrackingWindow time.Duration
+
+	// Each interval should be short for adapability.
+	// Less than 30 seconds is too sensitive,
+	// and greater than 5 minutes will make the metric numb
+	IntervalLength time.Duration
+}
+
+// DefaultConfig returns a config with values that have been tested and produce desirable results
+func DefaultConfig() TrustMetricConfig {
+	return TrustMetricConfig{
+		ProportionalWeight: 0.4,
+		IntegralWeight:     0.6,
+		TrackingWindow:     (time.Minute * 60 * 24) * 14, // 14 days.
+		IntervalLength:     1 * time.Minute,
+	}
+}
+
+// Ensures that all configuration elements have valid values
+func customConfig(tmc TrustMetricConfig) TrustMetricConfig {
+	config := DefaultConfig()
+
+	// Check the config for set values, and setup appropriately
+	if tmc.ProportionalWeight > 0 {
+		config.ProportionalWeight = tmc.ProportionalWeight
+	}
+
+	if tmc.IntegralWeight > 0 {
+		config.IntegralWeight = tmc.IntegralWeight
+	}
+
+	if tmc.IntervalLength > time.Duration(0) {
+		config.IntervalLength = tmc.IntervalLength
+	}
+
+	if tmc.TrackingWindow > time.Duration(0) &&
+		tmc.TrackingWindow >= config.IntervalLength {
+		config.TrackingWindow = tmc.TrackingWindow
+	}
+
+	return config
+}

p2p/trust/metric_test.go

@@ -0,0 +1,90 @@
+package trust
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestTrustMetricScores(t *testing.T) {
+	tm := NewMetric()
+
+	// Perfect score
+	tm.GoodEvents(1)
+	score := tm.TrustScore()
+	assert.Equal(t, 100, score)
+
+	// Less than perfect score
+	tm.BadEvents(10)
+	score = tm.TrustScore()
+	assert.NotEqual(t, 100, score)
+	tm.Stop()
+}
+
+func TestTrustMetricConfig(t *testing.T) {
+	// 7 days
+	window := time.Minute * 60 * 24 * 7
+	config := TrustMetricConfig{
+		TrackingWindow: window,
+		IntervalLength: 2 * time.Minute,
+	}
+
+	tm := NewMetricWithConfig(config)
+
+	// The max time intervals should be the TrackingWindow / IntervalLen
+	assert.Equal(t, int(config.TrackingWindow/config.IntervalLength), tm.maxIntervals)
+
+	dc := DefaultConfig()
+	// These weights should still be the default values
+	assert.Equal(t, dc.ProportionalWeight, tm.proportionalWeight)
+	assert.Equal(t, dc.IntegralWeight, tm.integralWeight)
+	tm.Stop()
+
+	config.ProportionalWeight = 0.3
+	config.IntegralWeight = 0.7
+	tm = NewMetricWithConfig(config)
+
+	// These weights should be equal to our custom values
+	assert.Equal(t, config.ProportionalWeight, tm.proportionalWeight)
+	assert.Equal(t, config.IntegralWeight, tm.integralWeight)
+	tm.Stop()
+}
+
+func TestTrustMetricStopPause(t *testing.T) {
+	// Cause time intervals to pass quickly
+	config := TrustMetricConfig{
+		TrackingWindow: 5 * time.Minute,
+		IntervalLength: 10 * time.Millisecond,
+	}
+
+	tm := NewMetricWithConfig(config)
+
+	// Allow some time intervals to pass and pause
+	time.Sleep(50 * time.Millisecond)
+	tm.Pause()
+	// Give the pause some time to take place
+	time.Sleep(10 * time.Millisecond)
+
+	first := tm.Copy().numIntervals
+	// Allow more time to pass and check the intervals are unchanged
+	time.Sleep(50 * time.Millisecond)
+	assert.Equal(t, first, tm.numIntervals)
+
+	// Get the trust metric activated again
+	tm.GoodEvents(5)
+	// Allow some time intervals to pass and stop
+	time.Sleep(50 * time.Millisecond)
+	tm.Stop()
+	// Give the stop some time to take place
+	time.Sleep(10 * time.Millisecond)
+
+	second := tm.Copy().numIntervals
+	// Allow more time to pass and check the intervals are unchanged
+	time.Sleep(50 * time.Millisecond)
+	assert.Equal(t, second, tm.numIntervals)
+
+	if first >= second {
+		t.Fatalf("numIntervals should always increase or stay the same over time")
+	}
+}

p2p/trust/store.go

@@ -0,0 +1,192 @@
+// Copyright 2017 Tendermint. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package trust
+
+import (
+	"encoding/json"
+	"sync"
+	"time"
+
+	cmn "github.com/tendermint/tmlibs/common"
+	dbm "github.com/tendermint/tmlibs/db"
+)
+
+const defaultStorePeriodicSaveInterval = 1 * time.Minute
+
+var trustMetricKey = []byte("trustMetricStore")
+
+// TrustMetricStore - Manages all trust metrics for peers
+type TrustMetricStore struct {
+	cmn.BaseService
+
+	// Maps a Peer.Key to that peer's TrustMetric
+	peerMetrics map[string]*TrustMetric
+
+	// Mutex that protects the map and history data file
+	mtx sync.Mutex
+
+	// The db where peer trust metric history data will be stored
+	db dbm.DB
+
+	// This configuration will be used when creating new TrustMetrics
+	config TrustMetricConfig
+}
+
+// NewTrustMetricStore returns a store that saves data to the DB
+// and uses the config when creating new trust metrics
+func NewTrustMetricStore(db dbm.DB, tmc TrustMetricConfig) *TrustMetricStore {
+	tms := &TrustMetricStore{
+		peerMetrics: make(map[string]*TrustMetric),
+		db:          db,
+		config:      tmc,
+	}
+
+	tms.BaseService = *cmn.NewBaseService(nil, "TrustMetricStore", tms)
+	return tms
+}
+
+// OnStart implements Service
+func (tms *TrustMetricStore) OnStart() error {
+	if err := tms.BaseService.OnStart(); err != nil {
+		return err
+	}
+
+	tms.mtx.Lock()
+	defer tms.mtx.Unlock()
+
+	tms.loadFromDB()
+	go tms.saveRoutine()
+	return nil
+}
+
+// OnStop implements Service
+func (tms *TrustMetricStore) OnStop() {
+	tms.BaseService.OnStop()
+
+	tms.mtx.Lock()
+	defer tms.mtx.Unlock()
+
+	// Stop all trust metric go-routines
+	for _, tm := range tms.peerMetrics {
+		tm.Stop()
+	}
+
+	// Make the final trust history data save
+	tms.saveToDB()
+}
+
+// Size returns the number of entries in the trust metric store
+func (tms *TrustMetricStore) Size() int {
+	tms.mtx.Lock()
+	defer tms.mtx.Unlock()
+
+	return tms.size()
+}
+
+// GetPeerTrustMetric returns a trust metric by peer key
+func (tms *TrustMetricStore) GetPeerTrustMetric(key string) *TrustMetric {
+	tms.mtx.Lock()
+	defer tms.mtx.Unlock()
+
+	tm, ok := tms.peerMetrics[key]
+	if !ok {
+		// If the metric is not available, we will create it
+		tm = NewMetricWithConfig(tms.config)
+		// The metric needs to be in the map
+		tms.peerMetrics[key] = tm
+	}
+	return tm
+}
+
+// PeerDisconnected pauses the trust metric associated with the peer identified by the key
+func (tms *TrustMetricStore) PeerDisconnected(key string) {
+	tms.mtx.Lock()
+	defer tms.mtx.Unlock()
+
+	// If the Peer that disconnected has a metric, pause it
+	if tm, ok := tms.peerMetrics[key]; ok {
+		tm.Pause()
+	}
+}
+
+// Saves the history data for all peers to the store DB.
+// This public method acquires the trust metric store lock
+func (tms *TrustMetricStore) SaveToDB() {
+	tms.mtx.Lock()
+	defer tms.mtx.Unlock()
+
+	tms.saveToDB()
+}
+
+/* Private methods */
+
+// size returns the number of entries in the store without acquiring the mutex
+func (tms *TrustMetricStore) size() int {
+	return len(tms.peerMetrics)
+}
+
+/* Loading & Saving */
+/* Both loadFromDB and savetoDB assume the mutex has been acquired */
+
+// Loads the history data for all peers from the store DB
+// cmn.Panics if file is corrupt
+func (tms *TrustMetricStore) loadFromDB() bool {
+	// Obtain the history data we have so far
+	bytes := tms.db.Get(trustMetricKey)
+	if bytes == nil {
+		return false
+	}
+
+	peers := make(map[string]MetricHistoryJSON, 0)
+	err := json.Unmarshal(bytes, &peers)
+	if err != nil {
+		cmn.PanicCrisis(cmn.Fmt("Could not unmarshal Trust Metric Store DB data: %v", err))
+	}
+
+	// If history data exists in the file,
+	// load it into trust metric
+	for key, p := range peers {
+		tm := NewMetricWithConfig(tms.config)
+
+		tm.Init(p)
+		// Load the peer trust metric into the store
+		tms.peerMetrics[key] = tm
+	}
+	return true
+}
+
+// Saves the history data for all peers to the store DB
+func (tms *TrustMetricStore) saveToDB() {
+	tms.Logger.Debug("Saving TrustHistory to DB", "size", tms.size())
+
+	peers := make(map[string]MetricHistoryJSON, 0)
+
+	for key, tm := range tms.peerMetrics {
+		// Add an entry for the peer identified by key
+		peers[key] = tm.HistoryJSON()
+	}
+
+	// Write all the data back to the DB
+	bytes, err := json.Marshal(peers)
+	if err != nil {
+		tms.Logger.Error("Failed to encode the TrustHistory", "err", err)
+		return
+	}
+	tms.db.SetSync(trustMetricKey, bytes)
+}
+
+// Periodically saves the trust history data to the DB
+func (tms *TrustMetricStore) saveRoutine() {
+	t := time.NewTicker(defaultStorePeriodicSaveInterval)
+	defer t.Stop()
+loop:
+	for {
+		select {
+		case <-t.C:
+			tms.SaveToDB()
+		case <-tms.Quit:
+			break loop
+		}
+	}
+}